Felbermayr gets moving with a TBM

The 78 tonne cutterhead is lifted at Augustinplatz in a tandem lifting operation using a 400 and a 250 tonne crane. Photo: Felbermayr

An overground move of an underground machine saw Austrian specialist Felbermayr combine its lifting and transport skills.

Having finished cutting a new tunnel section for Vienna’s U2 underground railway line, it was the job of local lifting and transport contractor Felbermayr, to relocate the giant tunnel boring machine named Debohra.

Herrenknecht built the TBM with a 7 metre diameter cutter head, a total weight of around 1,300 tonnes and an assembled length of 120 metres. Its 1.92 megawatt drive is the equivalent to 2,600 hp.

Felbermayr moved the main sections in a three-part operation, from Augustinplatz to Matzleinsdorfer Platz, a distance of around 11 km. Equipment used included wheeled mobile cranes lifting in tandem and a MAN four-axle tractor unit with ten-axle semi low-loader trailer for the transport.

The convoy crossing one of several inner-city intersections at night. Photo: Felbermayr

Trio of threes

Over a period of three nights Felbermayr made three lifts and three transports of three major components. First was the cutterhead drive unit weighing 73 tonnes, lifted and loaded using a 400 tonne.

One night later it was the turn of the 78 tonne cutterhead. Its dimensions were such that the component had to be lifted using the 400 and 250 tonne cranes lifting in a tandem operation.

On the third day, the TBM’s tail shield, weighing 34 tonnes and almost seven metres in diameter, was lifted and transported. “Such transports cannot be improvised; they are planned months in advance down to the smallest detail,” explained Thomas Daxelmüller, deputy branch manager at Lanzendorf and project manager on behalf of Felbermayr. “It’s not enough to simply lift the load and drive off. We have to consider every junction, every bottleneck, every height restriction beforehand.”

Goodnight Vienna

The four-axle MAN tractor manoeuvres its ten-axle semi low-loader trailer backwards into position at Matzleinsdorfer Platz for unloading. Photo: Felbermayr

After dark, as the pace of the city slowed down, the tandem lift began with slinging the load, pre-tensioning and load testing. The cutterhead was balanced at its centre of gravity and synchronised between both cranes, remaining stable until set down on the trailer. For the journey there were police vehicles, escort cars and Felbermayr specialists looking out obstacles along the route.

The transport route took the load past Lugner City, against the flow of traffic along the Gürtel and on towards Schönbrunn Palace. Finally, it was back into the city centre to Matzleinsdorfer Platz.

Closures at junctions were made, lamp posts and signage removed, and no-parking areas established. Around 3 a.m. the convoy reached its destination.

“When a seven-metre-wide component rolls through a metropolis, you can feel the scale of the project with every metre,” said Gabriel Asböck, division and project manager. “For onlookers, it might seem like a spectacle – for us, it means maximum precision and concentration.”

Guiding the large and awkward loads through the narrow streets and tight corners was no mean feat. “Lifting and transporting these components is like dancing the waltz,” Asböck commented. “Lead, posture, rotation – they must be internalised and executed precisely. If even one step is out of rhythm, the figure may topple. Only with a well-rehearsed team and excellent co-operation with the authorities can such choreography succeed.”

A gantry crane was used to lift the cutterhead and other components from the trailer. This was taking place at three o’clock in the morning. Photo: Felbermayr